低压无功补偿论文

本科生毕业设计（论文）题目：低压无功补偿器设计学生姓名：系别：专业年级：指导教师：摘要本课题研究以低压电网无功补偿改造为背景，研制了一种低压无功功率补偿控制器。作为一种非实时的无功补偿装置，该装置以定时的电网监测数据为依据，以城镇低压网(220V)的无功补偿为对象。本文主要研究了无功补偿对电网性能的改善，以及控制器的软硬件的配置。系统采用5189CAT单片机，该单片机是美国ATMEL公司生产的低电压，高性能的CMOS8位单片机，具有运算速度高，实时性好的特点；软件则使用汇编语言进行编译；人机操作界面采用LCD显示,显示效果较好；A/D转换采用0809ADC，是一款比较实用的A/D转换装置。该装置可跟踪电网无功功率的变化并自动补偿,实现了无功补偿装置的优化运行,具有体积小、原理简单、智能投切等优点。关键词：无功补偿；单片机；低电压AbstractWhatthisarticlestudiesisbasedonthealterationofreactivepowercompensationoflowvoltage,thendesignanequipmentforreactivepowercompensationoflowvoltage.Asakindofreactivepowercompensation,thisequipmentisbasisontheelectricalnetworkmonitordata,andprovidesreactivepowerforcity’slowvoltagepowergrids.Thisthesishasdiscussedtheimportanceofthereactivepowercompensationforthepowergrids,andintrodudedthehardwareandsoftwareofthecontroller.Thisdevice'shardwarecoreisAT89C51SCM,whichhasmanymeritssuchashighoperatingspeed.ThismonolithicintegratedcircuitisthelowvoltagewhichAmericanATMELCorporationproduces,ahighperformanceCMOS8monolithicintegratedcircuits;Thesoftwareusestheassemblylanguagetocarryonthetranslation;Theman-machineoperationcontactsurfaceusestheLCDdemonstration,thedemonstrationeffectisquitegood;A/DtransformationusesADC0809,itisasectionofquitepracticalA/Dswitchingdevice.Thisequipmentmaytracktheelectricalnetworkreactivepowerthechangeandtheautomaticcompensation,andthisinstallmenthasthevolumetobesmall,theprecisionishigh,thepricecomparedtothehighermerit.KeyWords:Reactivepowercompensation;SCM(SingleChipMicyoco);Lowvoltage目录摘要..............................................................................................................................1ABSTRACT...................................................................................................................0目录................................................................................................................................0第一章绪论..................................................................................................................11．1研究背景............................................................................................................11．2无功补偿装置的发展状况................................................................................21．3本课题主要研究的内容....................................................................................4第二章无功补偿的原理..............................................................................................52．1无功补偿的原理................................................................................................62．2低压电网中的几种无功补偿的方式................................................................92．3确定补偿容量的几种方法................................................错误!未定义书签。2．3．1从提高功率因数需要确定补偿容量............错误!未定义书签。2．3．2从降低线路有功损耗需要来确定补偿容量错误!未定义书签。2．3．3从提高运行电压需要来确定补偿容量........错误!未定义书签。2．4本章小结............................................................................错误!未定义书签。第三章硬件设计..........................................................................错误!未定义书签。3．1无功补偿装置的技术要求................................................错误!未定义书签。3．1．1补偿控制应符合技术条件：........................错误!未定义书签。3．1．2测量精度........................................................错误!未定义书签。3．1．3控制器原理....................................................错误!未定义书签。3．2硬件介绍............................................................................错误!未定义书签。3．2．1CPU.................................................................错误!未定义书签。3．2．2A/D转换器选型.............................................错误!未定义书签。3．2．3看门狗............................................................错误!未定义书签。3．2．4LCD显示........................................................错误!未定义书签。3．3模拟信号调理电路............................................................错误!未定义书签。3．3．1互感器信号转换及电流—电压转换电路....错误!未定义书签。3．3．2电压、电流采样及信号处理电路................错误!未定义书签。3．4输出控制电路....................................................................错误!未定义书签。3．5本章小结............................................................................错误!未定义书签。第四章软件设计........................................................................错误!未定义书签。4．1投切原则..............................................................................错误!未定义书签。4．2功率因数计算..................................................................................................264．3本章小结............................................................................错误!未定义书签。第五章总结与展望....................................................................................................29参考文献......................................................................................................................30致谢..............................................................................................................................21附录1：硬件结构图...................................................................................................22附录2：软件程序.......................................................................错误!未定义书签。1第一章绪论1．1研究背景目前，我国的电网，特别是广大的低压电网，普遍存在功率因数较低、电网线损较大的情况。导致此现象的主要原因是众多的感性负载用电设备设计落后，功率因数较低。比如我国